Prime Minister Theresa May could lose control of parliament in Britain’s June 8 election, according to a projection by polling company YouGov, raising the prospect of political turmoil just as formal Brexit talks begin.

The YouGov model suggested May would lose 20 seats and her 17-seat working majority in the 650-seat British parliament, though other models show May winning a big majority of as much as 142 seats and a Kantar poll showed her lead widening.

If the YouGov model turns out to be accurate, May would be well short of the 326 seats needed to form a government tasked with the complicated talks, due to start shortly after the election, on Britain’s divorce from the European Union.

A later poll, a separate regular survey carried out by YouGov for Thursday’s Times newspaper, showed May’s Conservative Party just three percentage points ahead of the Labour opposition, which has been eating into her lead since the start of the campaign.

The Conservatives were on 42 percent, down a point from last week, with Labour up three points, the YouGov survey said.

When May stunned politicians and financial markets on April 18 with her call for a snap election, opinion polls suggested she could emulate Margaret Thatcher’s 1983 majority of 144 seats or even threaten Tony Blair’s 1997 Labour majority of 179 seats.

But polls had shown May’s rating slipping over the past month and they fell sharply after she set out plans on May 18 to make some elderly people pay a greater share of their care costs, a proposal dubbed the “dementia tax” by opponents.